Wenger has acquired 20-year-old Rob Holding from Bolton Wanderers and he partnered midfielder Krystian Bielik in central defence in the 2-1 win over the MLS All-stars, but journalist Emanuele Giulianelli claimed the Gunners had been in contact with the player’s agent and now Sky Sky Deutschland have reported that talks are underway between the two clubs.

Valencia were believed to be willing to sell Mustafi if Arsenal met their £20.9m valuation of the 24-year-old centre-back, who has only just returned from holiday following his Euro 2016 commitments with Germany.

The former Hamburg and Everton defender, who joined Valencia from Sampdoria two years ago, has a £42.1million release clause in his contract, but Valencia could be willing to let him leave for just over £30million.

Mertesacker has returned to Germany during the week to undergo knee surgery and he will be missing for a “few months”, while Laurent Koscienly is yet to join the Arsenal squad as he enjoys a post-season break.

Calum Chambers and Gabriel Paulista are other defensive options for Wenger.